Light emitting device package

ABSTRACT

A light emitting device package including a light emitting device and a magnetic ring is provided. The magnetic ring surrounds the light emitting device for forming a magnetic source for applying a magnetic field to the light emitting device.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation application of and claims thepriority benefit of U.S. application Ser. No. 12/168,073, filed on Jul.4, 2008. The prior application Ser. No. 12/168,073 claims the prioritybenefit of U.S. provisional application Ser. No. 61/020,397, filed onJan. 11, 2008. The entirety of each of the above-mentioned patentapplications is hereby incorporated by reference herein and made a partof this specification.

BACKGROUND OF THE INVENTION

1. Technical Field

The invention generally relates to a light source and, in particular, toa light emitting device.

2. Background

Distinct from regular fluorescent lamps or incandescent lamps thatgenerate heat to emit light, semiconductor light emitting devices suchas light emitting diodes (LEDs) adopt the specific property ofsemiconductor to emit light, in which the light emitted by thesemiconductor light emitting devices is referred to as coldluminescence. The light emitting devices have advantages of longlifetime, light weight, high brightness, and low power consumption, suchthat the light emitting devices have been employed in a wide variety ofapplications, such as optical displays, traffic lights, data storageapparatus, communication devices, illumination apparatus, medicaltreatment equipments, and 3C products. Accordingly, how to improve thelight emitting efficiency of light emitting devices is an importantissue in this art.

FIG. 1 is a schematic cross-sectional view of a conventional LED.Referring to FIG. 1, the LED 100 is a vertical type LED, which includeselectrodes 110 and 120, and a light emitting layer 130. As shown in FIG.1, the tight lines represent high current density, and the area withmost number of lines is located between the electrodes 110 and 120.However, due to the congenital deficiency, the area with highest lightemitting efficiency is blocked by the electrode 110, such that theoverall light emitting efficiency of the LED 100 is adversely affected.

FIG. 2 is a schematic top view of another conventional LED. Referring toFIG. 2, the LED 200 is a horizontal type LED, which includes electrodes210 and 220. Because the current always transmits through a path withlowest resistance, the distribution of the current density isinhomogeneous between the electrodes 210 and 220, where the maindistribution of the current density is along the direct path between theelectrodes 210 and 220. Therefore, in order to increase the amount oflight emitted by the LED 200, the uniform current distribution area isneeded to be enlarged, such that the size of the LED 200 is enlarged.

Based on aforesaid description, it is concluded that the light emittingefficiency of the LED may be influenced by the following factors.

1. The area between the electrodes of the LED is not only the area withhighest current carrier density, but also the area producing mostphotons. However, the photons produced between the electrodes are mostlyblocked by the opaque electrode, such that the light emitting efficiencyis hard to be enhanced.

2. A current always transmits through a path with lowest resistance,which results in inhomogeneous luminance of the LED, such that the lightemitting efficiency and the size of the LED are also limited.

SUMMARY

According to an embodiment, a light emitting device package including alight emitting device and a magnetic ring is provided. The magnetic ringsurrounds the light emitting device for forming a magnetic source forapplying a magnetic field to the light emitting device, wherein themagnetic ring is not in electrical contact with the light emittingdevice.

According to an embodiment, a magnetic ring defines a containing spaceonly inside the magnetic ring. A containing space is surrounded by themagnetic ring, and at least a part of a light emitting device is locatedinside the containing space.

According to yet another embodiment, a magnetic ring surrounds a wholelight emitting device.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings are included to provide a furtherunderstanding of the invention, and are incorporated in and constitute apart of this specification. The drawings illustrate embodiments of theinvention and, together with the description, serve to explain theprinciples of the invention.

FIG. 1 is a schematic cross-sectional view of a conventional verticaltype light emitting diode (LED).

FIG. 2 is a schematic top view of a conventional horizontal type LED.

FIG. 3 is a schematic cross-sectional view of a light emitting devicepackage according to a first embodiment.

FIG. 4A is a schematic cross-sectional view of a light emitting devicepackage according to a second embodiment.

FIG. 4B is a schematic bottom view of a light emitting device in FIG.4A.

FIG. 5 is a graph showing the additional output power of the lightemitted by a light emitting device package applying a magnetic fieldaccording to one embodiment.

FIG. 6 is a graph showing the output power of the light emitted by alight emitting device applying a magnetic field according to oneembodiment of the invention.

FIG. 7 is a schematic cross-sectional view of a light emitting devicepackage according to a third embodiment.

FIG. 8 is a schematic cross-sectional view of the light emitting devicepackage according to a fourth embodiment of the present embodiment.

FIG. 9 is a schematic cross-sectional view of a light emitting devicepackage according to a fifth embodiment of the present embodiment.

FIG. 10 is a schematic cross-sectional view of a light emitting devicepackage according to a sixth embodiment.

FIG. 11 is a schematic cross-sectional view of a light emitting devicepackage according to a seventh embodiment.

FIG. 12 is a schematic cross-sectional view of a light emitting devicepackage according to an eighth embodiment of the present embodiment.

FIG. 13 is a schematic cross-sectional view of a light emitting devicepackage according to a ninth embodiment of the present embodiment.

FIG. 14 is a schematic cross-sectional view of a light emitting devicepackage according to a tenth embodiment.

FIG. 15 is a schematic cross-sectional view of a light emitting devicepackage according to an eleventh embodiment.

FIG. 16 is a schematic cross-sectional view of a light emitting devicepackage according to a twelfth embodiment.

FIG. 17 is a schematic cross-sectional view of a light emitting devicepackage according to a thirteenth embodiment.

FIG. 18 is a schematic cross-sectional view of a light emitting devicepackage according to a fourteenth embodiment.

FIG. 19 is a schematic cross-sectional view of a light emitting devicepackage according to a fifteenth embodiment.

FIG. 20 is a cross-sectional view of a light emitting device packageaccording to a sixteenth embodiment.

FIG. 21 is a cross-sectional view of a light emitting device packageaccording to a seventeenth embodiment.

DESCRIPTION OF THE EMBODIMENTS

Reference will now be made in detail to the present embodiments,examples of which are illustrated in the accompanying drawings. Whereverpossible, the same reference numbers are used in the drawings and thedescription to refer to the same or like parts.

In the present specification, the material of the semiconductor layersincludes III-V group compound semiconductor and/or II-VI group compoundsemiconductor. In addition, a reflector in the present specification isdefined as that when a light beam is perpendicularly incident on thereflector, the reflector reflects 30% or more of the light beam.

First Embodiment

FIG. 3 is a schematic cross-sectional view of a light emitting devicepackage according to a first embodiment. Referring to FIG. 3, the lightemitting device package 300 of the present embodiment includes a lightemitting device 310 and a magnetic source 320 is provided. The lightemitting device 310 includes a first doped type layer 312, a seconddoped type layer 314, and a light emitting layer 316. The light emittinglayer 316 is located between the first doped type layer 312 and thesecond doped type layer 314. In the present embodiment, the first dopedtype layer 312 is an n-type semiconductor layer, and the second dopedtype layer 314 is a p-type semiconductor layer. In other words, thelight emitting device 310 is a light emitting diode (LED). However, inother embodiments, the light emitting device 310 may also be a laserdiode. Alternatively, in still other embodiments, the first doped typelayer 312 and the second doped type layer 314 may be organic layers, andthe light emitting device 310 may be an organic light emitting diode(OLED).

In the present embodiment, the light emitting layer 316 is a p-njunction between the first doped type layer 312 and the second dopedtype layer 314. However, in other embodiments (not shown), the lightemitting layer 316 may be a quantum well layer between the first dopedtype layer 312 and the second doped type layer 314 or other appropriateactive layers. The magnetic source 320 is disposed beside the lightemitting device 310 for applying a magnetic field to the light emittingdevice 310. In more detail, the magnetic source 320 may directlycontact, be indirectly connected to, or not contact the light emittingdevice 310. The magnetic source 320 is, for example, an element withmagnetism, an electrically conducting coil, an electromagnet, or otherelements capable of generating the magnetic field.

In the present embodiment, the light emitting device package 300 furtherincludes a first electrode 330 and a second electrode 340. The firstelectrode 330 is disposed on a first surface 312 a of the first dopedtype layer 312. The second electrode 340 is disposed on a second surface314 a of the second doped type layer 314. In the present embodiment, thefirst surface 312 a and the second surface 314 a face away from eachother; that is to say, the light emitting device package 300 is avertical type light emitting device package. It should be noted that thefirst doped type layer 312 and the second doped type layer 314 may beexchanged by each other in other embodiments.

When a voltage is applied to the first electrode 330 and the secondelectrode 340, currents are generated which pass through the seconddoped type layer 314, the light emitting layer 316, and the first dopedtype layer 312. The interaction between the currents and the magneticfiled of the magnetic source 320 generates a Lorentz force on thecurrents, so as to push the currents along a direction away from theregion under the first electrode 330, such as the left in FIG. 3. Inthis way, the currents are not concentrated under the first electrode330 but spread along the direction away from the region under the firstelectrode 330, such that more proportion of photons 316 a generated inthe light emitting layer 316 are not blocked by the second electrode 340and exit the light emitting device 310 through the first surface 312 a,thus increasing the light emitting efficiency of the light emittingdevice package 300.

It should be noted that the number of the magnetic source 320 in theinvention is not limited to one. In other embodiment, the number of themagnetic sources may be more than one.

Second Embodiment

FIG. 4A is a schematic cross-sectional view of a light emitting devicepackage according to a second embodiment, and FIG. 4B is a schematicbottom view of a light emitting device in FIG. 4A. Referring to FIGS. 4Aand 4B, the light emitting device package 300′ is similar to the lightemitting device package 300 in FIG. 3, but the differences therebetweenare as follows. In the light emitting device package 300′, a firstelectrode 330′ is disposed on a first surface 312 a′ of a first dopedtype layer 312′ of an light emitting device 310′, and a second electrode340′ is disposed on a second surface 314 a′ of a second doped type layer314′. The first surface 312 a′ and the second surface 314 a′ face alongsubstantially the same direction; that is to say, the light emittingdevice package 300′ is a horizontal type light emitting device package.It should be noted that the first doped type layer 312′ and the seconddoped type layer 314′ may be exchanged by each other in otherembodiments.

In the light emitting device package 300′ of the present embodiment, theinteraction between the currents in the light emitting device 310′ andthe magnetic filed of the magnetic source 320 generates a Lorentz forcepushing the currents out of the direct paths between the first electrode330′ and the second electrode 340′, such that the currents are moreuniform, which makes photons 316 a′ emitted from a light emitting layer316′ more uniform. In this way, the surface area of the light emittingdevice 310′ be relatively small even if a larger area for emittinguniform light is needed.

In the present embodiment, the photons 316 a′ pass through the seconddoped type layer 314′ and are then transmitted to the outside away fromthe first surface 312 a′; that is to say, the light emitting devicepackage 300′ may be a flip chip package. However, in other embodiments,the photons 316 a′ may pass through the first doped type layer 312′ andthe first surface 312 a′ and are then transmitted to the outside; thatis to say, the light emitting device package 300′ may be a wire bondedchip package.

FIG. 5 is a graph showing the additional output power of the lightemitted by a light emitting device package applying a magnetic fieldaccording to one embodiment, where x axis coordinate refers to thecurrent injected to the light emitting device and y axis coordinaterefers to the output power of light emitted by the light emittingdevice. Referring to FIG. 5, with applying a 0.05 T magnetic field tothe light emitting device, when the amount of injected current isincreased, the obtained additional output power of light is alsoincreased (referring to the curve in FIG. 5 indicated by “output power(mW) with applied magnetic field of 0.05 Tesla), where an additional 15percent output power of light is obtained when injecting a 600 mAcurrent to the light emitting device when the curve indicated by “outputpower (mW) with applied magnetic field of 0.05 Tesla” is compared withthe curve indicated by “output power (mW) without applying magneticfield”. Specifically, the curve indicated by “output power (mW) withoutapplying magnetic field is gotten when no magnetic field is applied tothe light emitting device.

FIG. 6 is a graph showing the output power of the light emitted by alight emitting device applying a magnetic field according to oneembodiment, where x axis coordinate refers to the current injected tothe light emitting device and y axis coordinate refers to the outputpower of light emitted by the light emitting device. Referring to FIG.6, when the strength of the external magnetic field is increased, theobtained additional output power of light is also increased.

It should be noted herein that the strength of the external magneticfield applied to the light emitting package may be a constant value, atime-varying value, or a gradient-varying value, but is not limited tothem. In addition, the angle between the direction of the magnetic fieldand the light emitting direction is from 0 to 360.

Third Embodiment

FIG. 7 is a schematic cross-sectional view of a light emitting devicepackage according to a third embodiment. Referring to FIG. 7, the lightemitting device package 400 of the present embodiment is similar to theabove light emitting device package 300 in FIG. 3, but the differencesbetween them are as follows. The light emitting device package 400 ofthe present embodiment further includes a first carrier 410, a secondcarrier 420, and a heat sink 430. The first carrier 410 is disposed onthe second carrier 420, and the second carrier 420 is disposed on theheat sink 430. The first carrier 410 is, for example, a submount, andthe second carrier 420 is, for example, a slug. In the presentembodiment, at least one of the first carrier 410, the second carrier420, and the heat sink 430 has magnetism to from the magnetic source 320shown in FIG. 3. In the present embodiment, the heat sink 430 has aplurality of fins. However, in other embodiment, the heat sink 430 maynot have fins and be a block or otherwise shaped heat sink.Additionally, the shape of the fins of the heat sink 430 is not limited.Moreover, the heat sink 430 may have heat conductivity and optionallyhave electrical conductivity.

In the present embodiment, a connection layer 440 a is disposed betweenthe light emitting device 310 and the first carrier 410 for bonding thelight emitting device 310 and the first carrier 410. In addition, areflector 450 is disposed between the light emitting device 310 and thefirst carrier 410 for reflecting light from the light emitting device310, so as to increase the light emitting efficiency of the lightemitting device package 400. However, in other embodiments, thereflector 450 may also be disposed between the first carrier 410 and thesecond carrier 420. Additionally, in other embodiments, the lightemitting device 310 may be bonded directly on the first carrier 410without being bonded through the connection layer 440 a. In the presentembodiment a connection layer 440 b is disposed between the firstcarrier 410 and the second carrier 420 for bonding the first carrier 410and the second carrier 420. However, in other embodiments, the firstcarrier 410 may be bonded directly on the second carrier 420 withoutbeing bonded through the connection layer 440 b. In the presentembodiment, a connection layer 440 c is disposed between the secondcarrier 420 and the heat sink 430 for bonding the second carrier 420 andthe heat sink 430. However, in other embodiments, the second carrier 420may be bonded directly on or screwed on the heat sink 430 without beingbonded through the connection layer 440 c. Furthermore, in the presentembodiment, the connection layers 440 a, 440 b, and 440 c is, forexample, electrically conducting glue, insulating glue, heat dissipatingglue, metal glue, non-metal glue, metal bump, or other appropriatematerial.

It should be noted that the light emitting device package is not limitedto include the second carrier 420 and the heat sink 430. In otherembodiments, the light emitting device package may not include the heatsink 430, and at least one of the first carrier 410 and the secondcarrier 420 has magnetism to form the magnetic source. Alternatively,the light emitting device package may not include the second carrier 420and the heat sink 430, and the first carrier 410 has magnetism and is,for example, a submount or a slug.

Fourth Embodiment

FIG. 8 is a schematic cross-sectional view of a light emitting devicepackage according to a fourth embodiment of the present embodiment.Referring to FIG. 8, the light emitting device package 400 a of thepresent embodiment is similar to the above light emitting device package400 in FIG. 7, but the differences between them are as follows. It isnot limited that the at least one of the first carrier 410, the secondcarrier 420, and the heat sink 430 wholly has magnetism. Alternatively,there may be a portion of the at least one of the first carrier 410, thesecond carrier 420, and the heat sink 430 having magnetism to form themagnetic source.

For example, in the light emitting device package 400 a of the presentembodiment, a first carrier 410 a includes a first portion 412 and asecond portion 414 located on the first portion 412, a second carrier420 a includes a third portion 422 and a fourth portion 424 located onthe third portion 422, and a heat sink 430 a includes a fifth portion432 and a sixth portion 434 located on the fifth portion 432. One of thefirst portion 412 and the second portion 414 is a magnetic portion, andthe other is a non-magnetic portion. Additionally, one of the thirdportion 422 and the fourth portion 424 is a magnetic portion, and theother is a non-magnetic portion. Moreover, one of the fifth portion 432and sixth portion 434 is a magnetic portion, and the other is anon-magnetic portion.

In other embodiments, there may be two of the first carrier, the secondcarrier, and the heat sink each have a magnetic portion and anon-magnetic portion, while the other has a single portion with orwithout magnetism. Alternatively, there may be one of the first carrier,the second carrier, and the heat sink has a magnetic portion and anon-magnetic portion, and the others each have a single portion with orwithout magnetism.

Fifth Embodiment

FIG. 9 is a schematic cross-sectional view of a light emitting devicepackage according to a fifth embodiment of the present embodiment.Referring to FIG. 9, the light emitting device package 400 b of thepresent embodiment is similar to the above light emitting device package400 in FIG. 7, but the differences between them are as follows. In thelight emitting device package 400 b, a second carrier 420 b has a recess426, and the light emitting device 310 and the first carrier 410 islocated in the recess 426. In the present embodiment, the second carrier420 b is, for example, a slug, and includes a bottom portion 422 b and aside wall portion 424 b. The side wall portion 424 b is disposed on thebottom portion 422 b and surrounds the light emitting device 310 and thefirst carrier 410. In the present embodiment, both the side wall portion424 b and the first carrier 410 have magnetism to form two magneticsources, thus increasing the strength of the magnetic field applied tothe light emitting device 310, such that the light emitting efficiencyof the light emitting device package 400 b is further improved. Itshould be noted that the shape of the recess 426 is not limited to thatshown in FIG. 9, and may be otherwise shaped in other embodiments.

However, in other embodiment, the bottom portion 422 b may havemagnetism, and the side wall portion 424 b may not have magnetism.Alternatively, the second carrier 420 b may have only one portion withor without magnetism. That is to say, the bottom portion 422 b and theside wall portion 424 b may be integrally formed. Additionally, thefirst carrier 410 may not have magnetism.

Sixth Embodiment

FIG. 10 is a schematic cross-sectional view of a light emitting devicepackage according to a sixth embodiment. Referring to FIG. 10, the lightemitting device package 400 c of the present embodiment is similar tothe above light emitting device package 400 b in FIG. 9, but thedifferences between them are as follows. The light emitting devicepackage 400 c of the present embodiment does not have the second carrier420 b shown in FIG. 9. In addition, a first carrier 410 c has a recess416, and the light emitting device 310 is located in the recess 416.Moreover, the first carrier 410 c may be a submount or a slug, and havea bottom portion 412 c and a side wall portion 414 c. The side wallportion 414 c is disposed on the bottom portion 412 c, and surrounds thelight emitting device 310. In the present embodiment, the bottom portion412 c or the side wall portion 414 c has magnetism. However, in otherembodiments, the first carrier 410 c may have only one portion with orwithout magnetism. In the present embodiment, the connection layer 440 bis disposed between the first carrier 410 c and the heat sink 430 forbonding the first carrier 410 c and the heat sink 430.

Seventh Embodiment

FIG. 11 is a schematic cross-sectional view of a light emitting devicepackage according to a seventh embodiment. Referring to FIG. 11, thelight emitting device package 400 d of the present embodiment is similarto the above light emitting device package 400 in FIG. 7, but thedifferences are as follows. In the light emitting device package 400 d,a heat sink 430 d includes a fifth portion 432 d and a sixth portion 434d. The fifth portion 432 d has a recess 436 for containing the sixthportion 434 d. The second carrier 420 is disposed on both the magneticfifth portion 432 d and the sixth portion 434 d and crosses a boundary Bbetween the fifth portion 432 d and the sixth portion 434 d. In thepresent embodiment, the fifth portion 432 d is a non-magnetic portion,and the sixth portion 434 d is a magnetic portion. The heat conductivityof the non-magnetic portion is greater than the heat conductivity of themagnetic portion, such that a heat conduction path P is formed from thelight emitting device 310 to the fifth portion 432 d through the firstcarrier 410 and the second carrier 420. Since the heat conduction path Pdoes not passes through any magnetic material, such that the heatdissipation efficiency of the light emitting device package 400 d in thepresent embodiment is better.

However, in other embodiment, the fifth portion 432 d and the sixthportion 434 d may be magnetic portion and non-magnetic portion,respectively.

Eighth Embodiment

FIG. 12 is a schematic cross-sectional view of a light emitting devicepackage according to an eighth embodiment of the present embodiment.Referring to FIG. 12, the light emitting device package 400 e of thepresent embodiment is similar to the above light emitting device package400 in FIG. 7, but the differences between them are as follows. In thelight emitting device package 400 e, a heat conducting element 460 isdisposed between the light emitting device 310 and the first carrier 410for increasing heat dissipation rate from the light emitting device 310,and the heat conducting element 460 is, for example, a heat conductinglayer.

Ninth Embodiment

FIG. 13 is a schematic cross-sectional view of a light emitting devicepackage according to a ninth embodiment of the present embodiment.Referring to FIG. 13, the light emitting device package 400 f is similarto the above light emitting device package 400 in FIG. 7, but thedifferences between them are as follows. In the light emitting devicepackage 400 f, a magnetic element 470 is disposed on the first carrier410, and the light emitting device 310 is disposed on the magneticelement 470. The magnetic element 470 is, for example, a magnetic layer,and forms a magnetic source. All of the first carrier 410, the secondcarrier 420, and the heat sink 430 may have no magnetism. Alternatively,at least a portion of at least one of the first carrier 410, the secondcarrier 420, and the heat sink 430 may have magnetism.

Tenth Embodiment

FIG. 14 is a schematic cross-sectional view of a light emitting devicepackage 400 g according to a tenth embodiment. Referring to FIG. 14, thelight emitting device package 400 g of the present embodiment is similarto the above light emitting device package 400 in FIG. 7, but thedifferences between them are as follows. The light emitting devicepackage 400 g of the present embodiment further includes an encapsulant480 and a magnetic film 490. The encapsulant 480 wraps the lightemitting device 310 and the first carrier 410. In the presentembodiment, the material of the encapsulant 480 is, for example,silicone resin or other resin. Moreover, the encapsulant 480 may bedoped with or not doped with phosphor. The magnetic film 490 is disposedon the encapsulant 480 for forming the magnetic source. In the presentembodiment, the light emitting device package 400 g further includes alens 510 disposed on the magnetic film 490. Additionally, a secondcarrier 420 g has a recess 426 g for containing the light emittingdevice 310 and the first carrier 410 in the present embodiment.

In the present embodiment, all of the first carrier 410, the secondcarrier 420 g, and the heat sink 430 may have no magnetism. However, inother embodiments, at least a portion of at least one of the firstcarrier 410, the second carrier 420 g, and the heat sink 430 may havemagnetism.

Eleventh Embodiment

FIG. 15 is a schematic cross-sectional view of a light emitting devicepackage according to an eleventh embodiment. Referring to FIG. 15, thelight emitting device package 400 h of the present embodiment is similarto the above light emitting device package 400 g in FIG. 14, but thedifferences between them are as follows. In the light emitting devicepackage 400 h, a plurality of magnetic powders 482 are doped in theencapsulant 480 to form the magnetic source. In other embodiments, thelight emitting device package may not include the magnetic film 490, butmay include the magnetic powders 482.

Twelfth Embodiment

FIG. 16 is a schematic cross-sectional view of a light emitting devicepackage according to a twelfth embodiment. Referring to FIG. 16, thelight emitting device package 400 i of the present embodiment is similarto the above light emitting device package 400 b in FIG. 9, but thedifferences between them are as follows. In the light emitting devicepackage 400 i, a reflector 520 is disposed on the bottom portion 422 bof the second carrier 420 b and the side wall portion 424 b of thesecond carrier 420 b, i.e. on the inner surface 428 of the recess 426,for reflecting light from the light emitting device 310, thus increasingthe light emitting efficiency of the light emitting device package 400i.

Thirteenth Embodiment

FIG. 17 is a schematic cross-sectional view of a light emitting devicepackage according to a thirteenth embodiment. Referring to FIG. 17, thelight emitting device package 400 j of the present embodiment is similarto the above light emitting device package 400 c in FIG. 10, but thedifferences between them are as follows. In the light emitting devicepackage 400 j, a reflector 530 is disposed on the bottom portion 412 cof the first carrier 410 c and the side wall portion 414 c of the firstcarrier 410 c, i.e. on an inner surface 418 of a recess 416. In thepresent embodiment, the connection layer 440 b bonds the first carrier410 c and the heat sink 430.

Fourteenth Embodiment

FIG. 18 is a schematic cross-sectional view of an light emitting devicepackage according to a fourteenth embodiment. Referring to FIG. 18, thelight emitting device package 400 k is partly similar to the above lightemitting device package 400 g in FIG. 14, but the differences betweenthem are as follows. In the light emitting device package 400 k, a firstcarrier 410 k is a lead frame but not a submount as in FIG. 14. In thepresent embodiment, the first carrier 410 k has magnetism. In addition,an encapsulant 480 k wraps the light emitting device 310 and a part ofthe first carrier 410 k. In the present embodiment, the material of the480 k is, for example, epoxy resin, silicone resin or other resin.

Fifteenth Embodiment

FIG. 19 is a schematic cross-sectional view of an light emitting devicepackage according to a fifteenth embodiment. Referring to FIG. 19, thelight emitting device package 400 l is similar to the above lightemitting device package 400 k in FIG. 18, but the differences betweenthem are as follows. In the light emitting device package 400 l, aplurality of magnetic powders 482 l are doped in an encapsulant 480 l.In addition, a magnetic element 470 l is disposed on the first carrier410 k, and the light emitting device 310 is disposed on the magneticelement 470 l. In the present embodiment, the magnetic element 470 l is,for example, a magnetic layer. In addition, a connection layer 440 d maybe disposed between the light emitting device 310 and the magneticelement 470 l, and another connection layer 440 e may be disposedbetween the magnetic element 470 l and the first carrier 410 k.

In other embodiments, the light emitting device package may include themagnetic powder 482 l but not the magnetic element 470 l, and the firstcarrier 410 k has or does not have magnetism. Alternatively, the lightemitting device package may include the magnetic element 470 l but notthe magnetic powder 482 l, and the first carrier 410 k has or does nothave magnetism.

Sixteenth Embodiment

FIG. 20 is a cross-sectional view of a light emitting device packageaccording to a sixteenth embodiment. Referring to FIG. 20, the lightemitting device package 400 m of the present embodiment is similar tothe above light emitting device package 400 f in FIG. 13, but thedifferences therebetween are as follows. The light emitting devicepackage 400 m further includes a magnetic ring 540 surrounding the lightemitting device 310 for forming the magnetic source. In the presentembodiment, the first carrier 410 may or may not have magnetism. In anembodiment, the magnetic ring 540 surrounds the whole light emittingdevice 310.

Seventeenth Embodiment

FIG. 21 is a cross-sectional view of a light emitting device packageaccording to a seventeenth embodiment. Referring to FIG. 21, the lightemitting device package 400 n is similar to the above light emittingdevice package 400 m in FIG. 20, but the differences between them are asfollows. In the light emitting device package 400 n, a reflector 450 mis disposed on both the first carrier 410 and the inner surface 542 ofthe magnetic ring 540, so as to increase the light emitting efficiencyof the light emitting device package 400 n.

It should be noted that light emitting device 310 in the above lightemitting device packages 400 and 400 a˜400 n may be replaced by theabove light emitting device 310′ in FIG. 4A to form light emittingdevice packages in other embodiments.

To sum up, in the light emitting device package according to theembodiments, since the magnetic source is disposed beside the lightemitting device for applying a magnetic field to the light emittingdevice, the paths of currents in the light emitting device is changedinto better paths by the magnetic field, thus increasing the lightemitting efficiency of the light emitting device package.

When the light emitting device package according to the embodiments is avertical type light emitting device package, the magnetic fieldgenerates a Lorentz force on the currents in the light emitting deviceto push the currents along a direction away from the region under theelectrode. In this way, the currents are not concentrated under theelectrode but spread along the direction away from the region under theelectrode, such that more proportion of photons generated in the lightemitting layer are not blocked by the electrode, thus increasing thelight emitting efficiency of the light emitting device package.

When the light emitting device package according to the embodiments is ahorizontal type light emitting device package, the magnetic fieldgenerates a Lorentz force pushing currents out of the direct pathsbetween the first electrode and the second electrode, such that thecurrents in the light emitting device are more uniform, which makesphotons emitted from the light emitting layer more uniform. In this way,the surface area of the light emitting device may be relatively smalleven if a larger area for emitting uniform light is needed.

It will be apparent to those skilled in the art that variousmodifications and variations can be made to the structure withoutdeparting from the scope or spirit of the invention. In view of theforegoing, it is intended that the cover modifications and variations ofthis invention provided they fall within the scope of the followingclaims and their equivalents.

1. A light emitting device package comprising: a light emitting device;and a magnetic ring surrounding the light emitting device for forming amagnetic source for applying a magnetic field to the light emittingdevice, wherein the magnetic ring is not in electrical contact with thelight emitting device.
 2. The light emitting device package according toclaim 1 further comprising a carrier, wherein the magnetic ring and thelight emitting device are disposed on the carrier.
 3. The light emittingdevice package according to claim 2, wherein the carrier is a submountor a slug.
 4. The light emitting device package according to claim 2further comprising a connection layer connected between the carrier andthe light emitting device.
 5. The light emitting device packageaccording to claim 4, wherein the connection layer is insulating glue,heat dissipating glue, or non-metal glue.
 6. The light emitting devicepackage according to claim 4, wherein the connection layer iselectrically conducting glue, metal glue, or metal bump.
 7. The lightemitting device package according to claim 2 further comprising areflector disposed between the light emitting device and the carrier. 8.The light emitting device package according to claim 7, wherein thereflector is disposed on both the carrier and an inner surface of themagnetic ring.
 9. A light emitting device package comprising: a lightemitting device; and a magnetic ring surrounding the light emittingdevice for forming a magnetic source for applying a magnetic field tothe light emitting device, wherein the magnetic ring defines acontaining space only inside the magnetic ring, the containing space issurrounded by the magnetic ring, and at least a part of the lightemitting device is located inside the containing space.
 10. The lightemitting device package according to claim 9 further comprising acarrier, wherein the magnetic ring and the light emitting device aredisposed on the carrier.
 11. The light emitting device package accordingto claim 10, wherein the carrier is a submount or a slug.
 12. The lightemitting device package according to claim 10 further comprising aconnection layer connected between the carrier and the light emittingdevice.
 13. The light emitting device package according to claim 10further comprising a magnetic element is disposed between the carrierand the light emitting device.
 14. The light emitting device packageaccording to claim 10 further comprising a reflector disposed betweenthe light emitting device and the carrier.
 15. The light emitting devicepackage according to claim 14, wherein the reflector is disposed on boththe carrier and an inner surface of the magnetic ring.
 16. A lightemitting device package comprising: a light emitting device, comprising:a first doped type layer; a second doped type layer; and a lightemitting layer located between the first doped type layer and the seconddoped type layer; and a magnetic ring surrounding the whole lightemitting device for forming a magnetic source for applying a magneticfield to the light emitting device.
 17. The light emitting devicepackage according to claim 16 further comprising a carrier, wherein themagnetic ring and the light emitting device are disposed on the carrier.18. The light emitting device package according to claim 17, wherein thecarrier is a submount or a slug.
 19. The light emitting device packageaccording to claim 17 further comprising a magnetic element is disposedbetween the carrier and the light emitting device.
 20. The lightemitting device package according to claim 17 further comprising areflector disposed between the light emitting device and the carrier.21. The light emitting device package according to claim 20, wherein thereflector is disposed on both the carrier and an inner surface of themagnetic ring.